1. Field of the Invention
This invention generally relates to a method for forming a bonding connection in a semiconductor integrated circuit device, and in particular to a method for manufacturing a semiconductor integrated circuit device including a wire bonding connection.
2. Description of the Prior Art
It is common practice to use aluminum for interconnection lines in semiconductor integrated circuit devices. However, aluminum interconnection lines suffer from corrosion due mainly to the moisture content of the air, and such corrosion could cause malfunctioning of an integrated circuit. Under the circumstances, several approaches have been proposed to provide an enhanced humidity-resistant characteristic of a semiconductor integrated circuit device as follows.
(1) One approach would be to provide a plasma-produced nitride film as a passivation film. However, such a plasma-produced nitride film is poor in uniformity in thickness, which could adversely affect the performance of a transistor, such as fluctuations in the threshold voltage of a MOS transistor and in the amplification of a bipolar transistor.
(2) Another approach would be to use a dual-in-line package (DIP) as a package of a semiconductor integrated circuit device. However, as the size of a semiconductor integrated circuit device increases, there is a case in which use may not be made of a DIP and instead use must be made of a flat package, which is inferior in the humidity-resistant characteristic than the DIP package.
(3) A further approach would be to use silicon as added into aluminum interconnection lines. In this case, however, the overall resistance of interconnection lines is also increased.